{
  "mcpServers": {
    "opcua-modeler": {
      "command": "npx",
      "args": ["-y", "node-opcua-modeler-mcp-server"],
      "env": {
        "OPCUA_MODELER_API_KEY": "stfv_your_api_key_here"
      }
    }
  }
}

npx node-opcua-modeler-mcp-server

→ list_namespaces()
← [
    { "alias": "di", "name": "OPC UA for Devices", "uri": "http://opcfoundation.org/UA/DI/", "dependencies": [] },
    { "alias": "robotics", "name": "OPC UA for Robotics", "uri": "http://opcfoundation.org/UA/Robotics/", "dependencies": ["di", "ia"] },
    ...
  ]

→ resolve_dependencies({ aliases: ["machineTool"] })
← ["di", "ia", "machinery", "isa95JobControl", "machineryJobs", "machineTool"]

→ list_types({ alias: "robotics" })
← [
    { "browseName": "MotionDeviceType", "kind": "ObjectType", "subtypeOf": "di:ComponentType", ... },
    { "browseName": "AxisType", "kind": "ObjectType", "subtypeOf": "di:ComponentType", ... },
    ...
  ]   // 25 types

→ get_type_details({ alias: "robotics", browseName: "MotionDeviceType" })
← {
    "browseName": "MotionDeviceType",
    "kind": "ObjectType",
    "subtypeOf": "di:ComponentType",
    "interfaces": ["di:IVendorNameplateType", "di:ITagNameplateType"],
    "components": [
      { "browseName": "robotics:Axes", "nodeClass": "Object", "typeDefinition": "FolderType", "modellingRule": "Mandatory" },
      { "browseName": "robotics:PowerTrains", "nodeClass": "Object", "typeDefinition": "FolderType", "modellingRule": "Mandatory" },
      ...
    ],
    "properties": [
      { "browseName": "di:Manufacturer", "dataType": "LocalizedText", "modellingRule": "Mandatory" },
      { "browseName": "robotics:MotionDeviceCategory", "dataType": "MotionDeviceCategoryEnumeration", "modellingRule": "Mandatory" },
      ...
    ]
  }

→ search_types({ query: "temperature" })
← [
    { "alias": "glass", "browseName": "MotorTemperatureTooHighEventType", ... },
    { "alias": "padim", "browseName": "TemperatureMeasurementVariableType", ... },
    { "alias": "amb", "browseName": "OverTemperatureConditionClassType", ... }
  ]

→ find_engineering_unit({ query: "celsius" })
← { "symbol": "°C", "matchType": "alias", "confidence": 1 }

→ find_engineering_unit({ query: "revolutions per minute" })
← { "symbol": "rpm", "matchType": "alias", "confidence": 1 }

→ find_engineering_unit({ query: "bar" })
← { "symbol": "bar", "matchType": "exact", "confidence": 1 }

→ opcua_model_validate({ yaml: "namespaces:\n  di:\n..." })
← {
    "valid": true,
    "diagnostics": [
      { "severity": "warning", "code": "W001", "message": "...", "line": 42 }
    ]
  }

→ opcua_model_generate({ yaml: "namespaces:\n  di:\n...", include_docs: false })
← {
    "valid": true,
    "artifacts": {
      "nodeset2_xml": "PD94bWwg...",
      "symbols_csv": "bmFtZSxu..."
    },
    "diagnostics": []
  }

→ opcua_model_reverse({ xml: "<?xml version=..." })
← {
    "yaml": "namespaces:\n  di:\n...",
    "diagnostics": []
  }

→ opcua_model_create({ prompt: "A robotic welding cell with two robot arms, each having 6 axes, temperature monitoring on each motor" })
← {
    "success": true,
    "yaml": "namespaces:\n  di:\n  robotics:\n...",
    "attempts": 2,
    "diagnostics": [],
    "model": "gemini-2.5-pro",
    "tokens": { "input": 4200, "output": 1800 }
  }

→ opcua_model_create({ prompt: "A CNC lathe with spindle speed and temperature", forceSpecs: ["di", "cnc"] })
← {
    "success": true,
    "yaml": "namespaces:\n  di:\n  cnc:\n...",
    "attempts": 1,
    "diagnostics": [],
    "model": "gemini-2.5-pro",
    "tokens": { "input": 3500, "output": 1200 }
  }

┌──────────────────────────────────────────────────┐
│  node-opcua-modeler-mcp-server                   │
│                                                  │
│  LOCAL TOOLS (offline, free)                      │
│  ┌────────────────────────────────────────┐       │
│  │ catalog.json (1.7 MB)                  │       │
│  │ • 25 companion spec registries         │       │
│  │ • 589 type summaries + details         │       │
│  │ • 1,533 engineering units              │       │
│  └────────────────────────────────────────┘       │
│  6 tools → query the catalog                     │
│                                                  │
│  CLOUD TOOLS (via api.opcua-modeler.sterfive.io) │
│  4 tools → validate / generate / reverse / create│
│                                                  │
│  stdio transport (JSON-RPC)                      │
└──────────────────────────────────────────────────┘